Engine idling too high?

1971 CHEVROLET CAMARO
8,000 MILES • 5.3L • V8 • 2WD • AUTOMATIC
Avatar
JROB71
I recently LS swapped my car listed above and for some reason it idles high, I went through the fuel, checked spark. As soon as I let go of the brakes it wants to take off. I don't know what else to look for.
Jan 18, 2025 at 11:31 AM
Advertisement
Avatar
JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,193 POSTS
  • ASE Certified Mechanic
Hi,

When you say you swapped it, do you mean the engine was changed? Is it still carburated? If so, there should be a curb idle adjustment via the throttle control solenoid.

Let me know what you are working with.

Joe
Jan 18, 2025 at 7:11 PM
Avatar
JROB71
  • MEMBER
  • 6 POSTS
I LS swapped it 5.3.
Jan 18, 2025 at 7:12 PM
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,503 POSTS
  • ASE Certified Mechanic
Is it driven by wire, or does it have a throttle cable? Please go over this guide:

https://www.2carpros.com/articles/engine-idles-too-high

Please go over this guide and get back to us.
Jan 21, 2025 at 9:32 AM
Avatar
JROB71
  • MEMBER
  • 6 POSTS
Throttle cable.
Jan 21, 2025 at 10:52 AM
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,503 POSTS
  • ASE Certified Mechanic
Okay, try to start the engine without the cable just the return spring. Also, Is the IAC plugged in and working? Is there a way you can pull codes?
Jan 22, 2025 at 8:38 AM
Avatar
JROB71
  • MEMBER
  • 6 POSTS
I had no code, and yes IAC works. I'm thinking it's the cheap throttle body.
Jan 22, 2025 at 8:44 AM
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,503 POSTS
  • ASE Certified Mechanic
Yep, that will do it. Does this engine have an EGR valve? If so it can be stuck open. I would remove it and use this video to test it.

https://www.youtube.com/watch?v=DqUCbbKdWf4

Let us know what you find.
Jan 23, 2025 at 9:21 AM
Avatar
JROB71
  • MEMBER
  • 6 POSTS
Thank you.
Jan 23, 2025 at 9:26 AM
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,503 POSTS
  • ASE Certified Mechanic
You are welcome, please let us know what happens.
Jan 24, 2025 at 8:54 AM
Avatar
JROB71
  • MEMBER
  • 6 POSTS
I see no EGR Valve.
Jan 24, 2025 at 11:13 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.